Portable fire escape ladder

ABSTRACT

A portable fire escape ladder provides a window sill bracket with chains depending therefrom and a plurality of tubular rungs secured to the chains at spaced intervals therealong.

United States Patent 1 [111 3,834,492

Ronk [451 Sept. 10, 1974 PORTABLE FIRE ESCAPE LADDER [56] References Cited [75] Inventor: Hugo V. Ronk, Martinsburgh, W. UNITED STATES PATENTS 2,202,597 5/1940 .Myer 182/198 2 397 953 4/1946 Ellis [82/196 [73] Assrgnee: American La France Inc.,

g y, Ohio 3,075,612 1] 1963 Gould 182/196 [22] Filed: Aug. 27, 1973 Primary Examiner-Reinaldo P. Machado [21] AppL No: 392,125 Attorney, Agent, or Fzrm-Webster B. Harpman [57] ABSTRACT g 182/196 J g2 A portable fire escape ladrier provides a window sill [58] Field of Search u 1 82/196, 197 198 199, bracket with chains depending therefrom and a plurality of tubular rungs secured to the chains at spaced intervals therealong.

5 Claims, 8 Drawing Figures M n ,3 i V/IZ I3C//I6 IO E f 5 r19 Y J b L J 0 g PORTABLE FIRE ESCAPE LADDER BACKGROUND OF THE INVENTION 1. Field of the Invention:

This invention relates to escape ladders of the portable or emergency types that are positioned over a window sill of a window opening so as to depend therefrom on the exterior of a building wall.

2. Description of the Prior Art:

Prior structures of this type may be found in US. Pat. Nos. 146,274, 323,288, 1,608,054, 2,397,353, 2,979,154, 3,075,612 and 3,727,724.

This invention, while resembling the prior art structures, discloses an improvement in the tubular rungs and the manner in which their end portions are secured to the spaced chains which depend from the window sill bracket.

SUMMARY OF THE INVENTION A portable fire escape ladder comprises a window sill bracket having a pair of chains secured thereto and depending therefrom and a plurality of tubular rungs positioned between the chains and secured at their ends thereto in spaced relation to one another.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the portable fire escape ladder in position in a window opening in a building wall with parts broken away.

FIG. 2 is an enlarged vertical section on line 22 of FIG. 1.

FIG. 3 is an enlarged top plan view on line 33 of Figure.

FIG. 4 is a top plan view of the window sill brackets seen in FIG. 3 and showing the same in collapsed position.

FIG. 5 is a plan view of one end ofa rung in the portable fire escape ladder seen in FIG. 1 showing the same prior to attachment of a chain thereof.

FIG. 6 is an end view of the ladder rung seen in FIG. 5.

FIG. 7 is a side view of an end portion of a rung of the ladder of FIG. 1 showing the same secured to a chain thereof; and

FIG. 8 is an end view of the chain and rung seen in FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the form of the invention chosen for illustration the portable fire escape ladder may be seen in its entirety in FIG. 1 of the drawings wherein a building wall 10 having a window opening 11 therein and a window sill 12 supports a window sill bracket which is formed of a pair of similarly shaped, tubular members 13 spaced by a pair of sissors links 14. Each of the tubular members 13 has a horizontal section 13A adapted to engage the upper surface of the window sill 12, a downwardly and outwardly curved inner end 13B shaped to engage the inner surface of the wall 10 as best seen in FIG. 2 of the drawings and each of the tubular members 13 has a vertical section 13C, the lower end of which is inturned and adapted to engage the outer surface of the wall 10. Both the inner ends and the outer ends of the similarly shaped tubular members 13 are provided with caps 15 and both of the similarly shaped tubular members 13 of the window sill bracket are provided with U-sha'ped hooks 16 in their vertical sections 13C, as best seen in FIG. 2 of the drawings, to which the upper ends of a pair of chains 17 are attached. The hooks 16 engage spaced, vertical apertures in the tubular members 13 and one end of each of the hooks I6 is threaded and provided with a nut 18 to secure the same in position as shown.

By referring again to FIG. 1 of the drawings. it will be seen that when the window sill bracket 13 is positioned on the window sill 12 with the vertical sections 13C thereof spaced outwardly from the outer surface of the building wall 10, the pair of chains 17 will depend from the hooks 16. A plurality of tubular light metal rungs 19 are secured at their ends to the chains 17 so as to be horizontally disposed therebetween and vertically spaced with respect to one another. The plurality of rungs l9 securely fasten to the pair of chains 17 which are in turn held by the window sill brackets 13 form a lightweight, portable fire escape ladder.

By referring now to FIG. 3 of the drawings, the horizontal portions 13A of the window sill bracket 13 may be seen joined to one another by the sissors links 14 which are in turn pivoted to each other at their innermost ends by a pivot 20. The outermost ends of the sissors links 14 are each pivoted to the respective, horizontal section 13A of the window sill bracket 13 by pivots 21. The sissors links 14 serve to hold the window sill brackets 13 in properly spaced position which spacing matches the length of the rungs 19 hereinbefore described.

When the portable fire escape ladder is collapsed and folded up for storage, the window sill brackets 13 move into side by side position as shown in FIG. 4 of the drawings.

By referring now FIGS. 5, 6, 7 and 8 of the drawings, the configuration of the rungs l9 and in particular their end sections which join the chains 17 may be seen.

In FIG. 5 one end of a tubular rung 19 may be seen to have been flattened as at 22 with the flattened end portion bent at right angles to form a perpendicular section 23. A notch 24 is formed on the vertical fold line between the flattened end 22 and the perpendicular section 23, the notch being formed from the lower surface of the flattened end 22 upwardly to approximately the middle section thereof so as to form an outwardly and downwardly curving configuration in the perpendicular section 23..

By referring to FIG. 6 of the drawings, which is an end view on FIG. 5, it will be seen that this perpendicular section 23 is formed at right angles to the axial center line of the tubular rung 19.

By referring now to FIG. 7 it will be seen that the perpendicular section 23 has been positioned through the lower portion of a figure-eight link in one of the chains 17 and the perpendicular portion 23 then bent into close engagement with the flattened end 22 of the rung 19 with the notch 24 permitting the lower portion of the figure-eight link of the chain 17 to emerge just below the axial center line of the rung 19 where the link of the chain is engaged by the upper end of the next figure-eight link of the chain therebelow.

In FIG.8 of the drawings an end view of the rung 19 shows the final secured position of the perpendicular section 23 in abutment against the flattened end 22 of the rung 19 and it will be seen that the arrangement is such that the rung 19 cannot rotate on its axis relative to the chain 17 to therefore provide a stable and secure step for a person using the portable fire escape ladder.

Those skilled in the art will observe that the window sill bracket parts 13 and the rungs 19 may be made of lightweight metal tubing so that the weight of the complete ladder is little more than that of the two chains 17 which form the main support elements thereof.

The above described structure provides a relatively inexpensive, lightweight, portable fire escape ladder that can be easily handled and placed in position in a window opening of a building to provide a safe and secure fire escape.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention.

Having thus described my invention what I claim is:

tions therein with transversely narrow sections therebctween, said outer sections being engaged in links ofsaid chains and folded backwardly into engagement with said inner sections.

2. The portable fire escape ladder of claim 1 and wherein said notches extend transversely less than half the width of said flattened end portions.

3. The poratble fire escape ladder of claim 1 and wherein the means engagable on said window sill consists of a pair of brackets having oppositely disposed downturned and inturned end portions, said chains being secured to one of said pairs of downturned end portions.

4. The portable fire escape ladder set forth in claim 1 and wherein said chains have elongated figure-eight shaped links and said narrow sections of said end portions are at least half the width of said end portions and engaged in said elongated figure-eight shaped links.

5. The portable fire escape ladder set forth in claim 1 and wherein said chains have elongated figure-eight shaped links and said outer sections of said flattened end portions are of substantially greater transverse width than the openings defined by said elongated figure-eight shaped links so that said links engage said notches and said outer sections form hooks engaged in said links. 

1. A poratble fire escape ladder consisting of a pair of chains, means engagable on a window sill of a window opening supporting said chains and a plurality of rungs positioned between said chains, each of said rungs being formed of a tubular member the end portions of which are flattened so as to close the same and partially notched transversely substantially midway of the flattened portions so as to form inner and outer sections therein with transversely narrow sections therebetween, said outer sections being engaged in links of said chains and folded backwardly into engagement with said inner sections.
 2. The portable fire escape ladder of claim 1 and wherein said notches extend transversely less than half the width of said flattened end portions.
 3. The poratble fire escape ladder of claim 1 and wherein the means engagable on said window sill consists of a pair of brackets having oppositely disposed downturned and inturned end portions, said chains being secured to one of said pairs of downturned end portions.
 4. The portable fire escape ladder set forth in claim 1 and wherein said chains have elongated figure-eight shaped links and said narrow sections of said end portions are at least half the width of said end portions and engaged in said elongated figure-eight shaped links.
 5. The portable fire escape ladder set forth in claim 1 and wherein said chains have elongated figure-eight shaped links and said outer sections of said flattened end portions are of substantially greater transverse width than the openings defined by said elongated figure-eight shaped links so that said links engage said notches and said outer sections form hooks engaged in said links. 